METHOD FOR PRODUCING GLASS BLANK FOR MAGNETIC DISC, METHOD FOR PRODUCING GLASS SUBSTRATE FOR MAGNETIC DISC, AND GLASS BLANK FOR MAGNETIC DISC

摘要

METHOD FOR MANUFACTURING GLASS BLANK FOR MAGNETIC DISK, METHOD FOR MANUFACTURING GLASS SUBSTRATE FOR MAGNETIC DISK, GLASS BLANK FOR MAGNETIC DISKA method for manufacturing a glass blank for magnetic disk and a method for manufacturing a glass substrate for magnetic disk are provided which are capable of producing a glass blank for magnetic disk having a good surface waviness by press forming. The method includes a forming process of press-forming a lump of molten glass using a pair of dies, wherein in the forming process, press forming is performed using thermally equalizing means for reducing a difference in temperature in the press forming surface of the die during pressing of the molten glass.Figure 4